Triangles — Class 10 Mathematics NCERT Solutions (Free)

Free step-by-step NCERT solutions for Class 10 Mathematics chapter "Triangles" — 9 important questions with detailed answers for CBSE board exam preparation.

TL;DR: Free step-by-step NCERT solutions for Class 10 Mathematics chapter "Triangles" — 9 important questions with detailed answers for CBSE board exam prepa…

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Key Questions Covered:

  1. State and explain the Basic Proportionality Theorem (Thales' Theorem). What d…
  2. Two triangles ABC and PQR are similar. If AB = 4 cm, BC = 6 cm, CA = 5 cm, an…
  3. In triangle ABC, DE || BC where D is on AB and E is on AC. If AD = 3 cm, DB =…
  4. + 6 more questions in the full chapter

Solutions Summary:

Question Status
State and explain the Basic Proportionality Theorem (Thal… ✓ Solved
Two triangles ABC and PQR are similar. If AB = 4 cm, BC =… ✓ Solved
In triangle ABC, DE || BC where D is on AB and E is on AC… ✓ Solved

Showing 3 of 9 questions

Q1: State and explain the Basic Proportionality Theorem (Thales' Theorem). What does it tell us about similar triangles?

Basic Proportionality Theorem (BPT): If a line is drawn parallel to one side of a triangle, then it divides the other two sides in the same ratio. Statement: In triangle ABC, if DE || BC (DE is parallel to BC), where D is on AB and E is on AC, then: AD/DB = AE/EC Explanation: - The parallel line D...

Q2: Two triangles ABC and PQR are similar. If AB = 4 cm, BC = 6 cm, CA = 5 cm, and PQ = 6 cm, find QR and RP.

Given: Triangle ABC ~ Triangle PQR AB = 4 cm, BC = 6 cm, CA = 5 cm PQ = 6 cm Find: QR and RP Step 1: Since ABC ~ PQR, the corresponding sides are proportional. Corresponding sides are: AB ↔ PQ, BC ↔ QR, CA ↔ RP Step 2: Write the ratio of similarity. AB/PQ = BC/QR = CA/RP = k (ratio of similarity)...

Q3: In triangle ABC, DE || BC where D is on AB and E is on AC. If AD = 3 cm, DB = 6 cm, and AE = 2 cm, find EC.

Given: Triangle ABC with DE || BC D is on AB, E is on AC AD = 3 cm, DB = 6 cm, AE = 2 cm Find: EC Step 1: Apply Basic Proportionality Theorem. Since DE || BC, we have: AD/DB = AE/EC Step 2: Substitute the known values. 3/6 = 2/EC Step 3: Solve for EC. 1/2 = 2/EC EC = 2 × 2 = 4 cm Answer: EC = 4...

Showing 3 of 9 questions. Visit the full page for complete solutions.